Many frying pans, saute pans, sauce pans and other cookware are sold without an accompanying lid or cover. Further, when a pan is sold with a cover, often the cover is either lost or broken before the working life of the pan has ended. Thus, there is a market for, and a need for, replacement covers for most types of cookware.
When designing replacement covers for cookware, a cover manufacturer is confronted with the problem of standard sizes of cookware that vary in diameter from manufacturer to manufacturer though they are nominally the same size and are marketed as such. Specifically, a 10-inch frying pan made by one manufacturer will be slightly larger or smaller in diameter than a 10-inch frying pan made by a second manufacturer. Further, the diameters and thicknesses of the rims of cookware may vary from model to model. For example, frying pans are generally made of a thicker material than sauce pans. Finally, the upper rims of pans vary in configuration. Some upper rims are relatively vertical, some are flared outwardly and others are beaded. Variations in the rim design will cause variations in the diameter of the rim.
The Cookware Manufacturers Association sets standards for cookware sizes. Cookware items calling for a diameter measurement should measure in inches (or centimeters) as indicated on the label with allowable manufacturing tolerances of 1/4 inch (or 6 millimeters). For example, to be in tolerance, a 10 inch frying pan may range from about 9.75 inches to 10.25 inches.
The problem arises when a consumer purchases replacement or additional covers for the cookware he or she owns. A 10-inch frying pan cover may not fit a 10-inch sauce pan and a 10-inch frying pan cover made by a first manufacturer may not fit a 10-inch frying pan made by a second manufacturer. Simply put, cookware covers are not presently interchangeable due to variations in pan diameters that occur from model to model and manufacturer to manufacturer.
Thus, there is a need for covers and replacement covers for cookware that will comfortably fit the standard size cookware produced by a variety of manufacturers and fit all the models of each standard size. For example, there is a need for a replacement cover for 10-inch cookware that will fit 10-inch cookware made by all manufacturers and also fit the 10-inch frying pans, 10-inch sauce pans and 10-inch stock pots made by all manufacturers.
In addition to the need generally to provide a cover which will fit pans of nominally the same but actually different dimensions, it is highly desirable that such a cover be so constructed as to snugly fit the container top with which it is used. In order to avoid excessive looseness between the container top and the cover it is desirable, if at all possible, to have the outside diameter of the container form a close fit with an inwardly-facing vertical surface of the universal cover, or the inside surface of the container form a close fit with an outwardly-facing vertical surface of the cover.
The provision of a snug, though not vapor-proof, fit is desirable for many reasons including the elimination of an annoying rattle which can occur if the container is filled with a liquid to nearly its top edge and a vigorous boil is created; the force of the boil often has a tendency to jiggle sideways or lift and drop the lighter, unrestrained cover which can generate a continuous rattle which is displeasing to the ear. If there is a snug, or simply a close fit between adjacent, relatively vertical surfaces on the cover and the container, the above-described annoying tendency to rattle is totally eliminated or at least significantly reduced.
Another advantage in having snug or at least close fitting surfaces between adjacent vertical surfaces on the container and a universal cover is to reduce spillage during handling of the container-cover combination during use. When, for example, a container-cover assembly is full nearly to overflowing with a liquid, the snug or close fit of the container and cover minimizes the spill over tendency of the liquid in the container. With a snug fit for example, the movement of liquid in a nearly filled container toward a side wall area due to a jarring, or tipping during transfer due to lack of hand strength by the user, will follow the same motion as does a wave when it splashes against a vertical sea wall; the uppermost liquid may rise but is largely or entirely restrained from rising up to and over the top of the vertical surface.
Prior workers in the art have recognized the need but the proposed solutions have fallen far short of meeting the need. Dantel (U.S. Pat. No. 1,310,981) for example, discloses a cover suitable for a number of different sized pots, but Dantel's rim "b" is so wide that only a small percentage of the pots with which it would be used would place adjacent non-horizontal surfaces in close juxtaposition with one another, and even if a particular pot-cover combination did achieve a close proximity of adjacent surfaces on the pot and cover, the substantial incline of the non-vertical portion of Dantel's cover would preclude a snug or even a close fit and hence the advantages achieved herein by applicant's construction would not be obtainable.
Foster (U.S. Pat. No. 2,247,230) also discloses a cover which is said to be reusable with containers of different diametrical dimensions. The Foster structure, however, is designed and intended to have a mode of operation directly contrary to the mode of operation of the herein disclosed invention. Thus, in Foster, no substantially vertically oriented surfaces are provided on the cover within the intended range of pot diameter with which the Foster cover is to be used, and hence the possibility of a snug fit, or even a close fit, between adjacent generally vertically oriented surfaces on a pot and Foster's cover would be mechanically possible. The Foster design is no doubt quite efficient for its intended purpose which is to facilitate the removal of liquids from the container, as would be the case when the pot-cover was tipped 90.degree. to drain the cooking water away from potatoes, but, as is obvious from the foregoing, this feature is directly contrary to what applicant seeks to guard against which is the boil-over of liquids from the container and to minimize if not eliminate the rattle which would inevitably occur between Foster's cover 12 and pot 11 when a vigorous boiling action is in progress with the boiling liquid very near the top of the pot 11. In effect, Foster teaches directly contrary to the herein described concept.
Thus, the need for a cover which is, in effect, universally reusable with all containers having the same nominal size, and which will act to retain liquid in the container rather than facilitate its egress has remained unsolved by prior workers until now.
It will be understood that applicant's invention is not a true universal cover in the sense that one structurally rigid cover fits all sizes of containers, i.e. 6 inch, 8 inch, 10 inch and 12 inch containers. Rather, applicant's cover is universal in the sense that it makes a snug or close fit with all or a very large majority portion of containers of the same nominal size; i.e. all 6 inch containers or all 8 inch containers etc., but not all 6 inch and 8 inch containers.